There should be a law that gives allowances for breezy in-the-moment promises...
Easy solution....don't make em...can't break em.
Why would someone make a promise they do not intend to keep or cannot uphold in it's entirety to begin with? If you can't agree with it in the long run, then don't make it at all. I don't make a promise that I can't or won't keep. If you want flexibility, then put that condition as part of it from the beginning. I don't think laws need to get involved in this either.
That's why I think carefully before ever agreeing on something, never give in to pressure to say yes.
I rarely make promises because it's as if the entire universe turns against you the moment you even consider mouthing the word.
Should some unfortunate soul make this rookie mistake, they'll bear witness to a marvelous spectacle wherein mother nature and all her creatures seemingly unleash a full frontal assault to delay, interfere with or downright cripple them and all their futile efforts to fulfill said commitment. Muhuwhahahaha!!!
I completely agree, something said in the moment might need a little wiggle room, just like every rule has it's exceptions... promises made in the moment usually need a few exceptions as well.